I do look at ads in my WW magazines, but only the larger ads that are interspersed with the articles. I skip right past the advertising sections at the end. If I'm looking for something specific, then right to google.
My company gets nearly all our initial sales through Google. Your search ranking is important - and this is a relatively difficult thing to do well.
It sounds like you want to sell to a particular niche. If that niche was, for example, selling guitar body blanks, then you would want to figure what search terms guitar builders use to search. You would want to frequent guitar-building forums. Ideally, you would be a guitar player and build your own guitar...or partner with someone who fits the bill. Then showcase the guitar on the forums and mention "BTW, you can get beautiful wood like this from me". If there are prominent, respected builders on the forum, you might give them some blanks, gratis, and hope that they build a beautiful guitar and give you a mention.
Note that print advertising can be very effective if you can reach your target customers effectively AND create an ad that really works. In the above example, a luthiers magazine could be very effective. "Guitar Player weekly", not so much (what percentage of players builds their own?...not many).
Find a way to get potential customers to subscribe to a newsletter, so you can touch them frequently with news and special deals. Use lots of pictures, if relevant. People respond to visuals more than text.
And of course, be sure you know what your selling angle is. It is low price? Great service? excellent quality? It can't be all three...and few companies manage two of the three. Pick one and focus on it.
This isn't really what you asked, but I highly recommend the book
Four Steps to the Epiphany by Stephen Blank, about customer development. His examples are based on the software industry, but the theory applies to nearly any business. The first five chapters are an excellent read (I haven't finished it yet).
Just my 2c
Chris